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101.
OBJECTIVE: To determine epidemiologic, clinical, and pathologic characteristics of inflammatory mammary carcinoma (IC) in dogs. DESIGN: Retrospective study. ANIMALS: 33 dogs with IC and 153 dogs with malignant mammary tumors other than IC. PROCEDURES: Medical records were reviewed, and signalment, history, physical examination findings, and results of thoracic radiography and necropsy were obtained. RESULTS: 33 of 436 (7.6%) dogs examined at a veterinary teaching hospital because of dysplasia or tumors of the mammary glands and 33 of 186 (17.7%) dogs with at least 1 malignant tumor had IC. Thirty-two of the 33 dogs were sexually intact. Dogs with IC were significantly older than were dogs with other malignant mammary tumors, and in dogs with IC, the tumor was initially noticed a mean of 52 days after the beginning of the last observed estrus, whereas in dogs with other mammary tumors, the tumor was initially noticed a mean of 137 days after the beginning of the last observed estrus. Dogs with IC were more likely to be anorectic and to have generalized weakness, weight loss, and thoracic metastases. Dogs with IC survived a mean of 25 days with palliative treatment. Histologically, involvement of dermal lymphatic vessels was identified in 14 of 19 (74%) dogs with IC. Two clinical forms of IC (primary and secondary) were identified. Dogs with primary IC had a worse clinical condition. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that IC is an uncommon but distinct entity in dogs. A histologic finding of dermal lymphatic involvement should be considered a hallmark for the pathologic diagnosis of IC in dogs.  相似文献   
102.
肉鸭皮脂作为一个数量性状进行选择是有效的、可行的,本文从营养、饲养管理、遗传各因素与皮脂的关系探讨降低皮脂的可行性。  相似文献   
103.
An experiment was designed to evaluate the effects of estradiol‐17β (E17β) on follicular wave dynamics and ovulatory response in Holstein heifers receiving either a progestogen ear‐implant (Crestar®; Intervet International b.v. Boxmeer, The Netherlands) or an intravaginal progesterone‐releasing device [controlled internal drug release‐bovine device (Eazibreed, CIDR‐B®; Bodinco BV, Alkmaar, The Netherlands)]. For comparison, another group of heifers was also synchronized using Crestar plus an injection of estradiol valerate (EV) and norgestomet as recommended by the pharmaceutical company. Twenty 20–22‐month‐old cycling Holstein heifers were allocated to one of the following treatment groups at random stages of the oestrous cycle: (I) simultaneous insertion of Crestar and intramuscular injection of 3 mg norgestomet and 5 mg EV (Crestar 9 + EV 9); (II) simultaneous insertion of Crestar and intramuscular injection of 5 mg E17β (Crestar 9 + E17β 9); (III) insertion of Crestar followed 2 days later by intramuscular injection of 5 mg E17β (Crestar 9 + E17β 7); or (IV) insertion of CIDR‐B device followed 2 days later by intramuscular injection of 5 mg E17β (CIDR 9 + E17β 7). The CIDR‐B or Crestar implants were removed after 9 days and all heifers received 500 μg Cloprostenol (Estrumate®, Pitman‐Moore Nederland BV, Houten, The Netherlands). Ovarian ultrasonographic examinations were performed once daily during the synchronization period using a B‐mode scanner equipped with a 7.5 MHz linear‐array transrectal transducer. In addition, heifers were scanned every 12 h after implant/device withdrawal until 3 days after ovulation in order to monitor follicular activity, detect ovulation and subsequent early luteal formation. Detection of oestrus was performed every 6 h for 4 days after device/implant removal. Oestrus was observed 24–32 h before ovulation in all heifers. The mean hours interval from treatment withdrawal to ovulation was not significantly different (84.0 ± 16.5, 77.6 ± 4.1, 73.6 ± 4.1 and 64.0 ± 4.4 h for treatments I, II, III and IV, respectively; p > 0.1). However, the variance for heifers treated with EV + norgestomet was significantly larger (Levene’s Test; p < 0.01) than those treated with E17β. All E17β treatments resulted in dominant follicle suppression and a new wave emerged 4.1 days after treatment compared with 6.6 days for the EV + norgestomet treatment (p < 0.05). The time from emergence of the new ovulatory wave to ovulation was longer for the new wave that emerged after E17β treatment (9.2 ± 0.3 days) than after EV + norgestomet treatment (6.9 ± 0.4 days; p < 0.05). The results of this study suggest that the four treatments used were effective in inducing synchronous behavioural oestrus and ovulation. However, a higher degree of oestrus and ovulation synchrony was observed in heifers treated with E17β than in heifers treated with EV + norgestomet. Synchronization treatments with exogenous E17β or EV + norgestomet at the time of progestin device insertion (Crestar or CIDR‐B) or 2 days later in heifers can regulate a different emergence pattern of ovarian follicular development in randomly cyclic heifers. The E17β was effective in inducing follicular suppression and resulted in the consistent emergence of a new follicular wave.  相似文献   
104.
退耕还林管理模式的创新   总被引:1,自引:0,他引:1  
退耕还林工程是我国正在实施的林业重点生态工程之一,依靠政策牵引、行政推动、严格检查的管理模式很难使这项涉及面宽、运行复杂的重大工程快速持续地推进.工程的实施应根据时代发展的要求,在人本主义理念的指导下,构建以激励机制为核心的市场化管理模式.  相似文献   
105.
石灰性土壤的电超滤(EUF)特性主要是浸提时因需控制电流而必须大大降低电压。在一定范围内,降压程度与土壤 CaCO_3%有密切关系。控流限额愈低,电压需成比例地下降,但土壤EUF-值减小不多。电流控制在一定值时,离子的解吸总量亦为定值。控流主要控制了各石灰性土壤解吸/溶解份额特大的 Ca+Mg 量近于定值,对于含量小的其他养分离子则并无多大影响,仍可区辨各土壤间的差别。通过冬小麦盆栽试验和有关化学测试法等方面的相关研究,表明采用国际通用的5g 土样和控电流方法测定 EUF-K 和-P 等有效养分,对于石灰性土壤也是可行的,但其EUF-(Ca+Mg)值则毫无植物营养有效性的意义。土壤 EUF 值只是一种指数,并非真正的解吸离子量。石灰性土壤 EUF-K 值因浸提时降压控流而略低,80℃时5min 内解吸的钾不一定是非交换性钾。由于 Ca-P 和 CaCO_3在高温高电压时浸出较多,故石灰性土壤 EUF-P 和-(Ca+Mg)的80℃值/20℃值之比,与酸性土壤或非石灰性土壤相比要大得多。  相似文献   
106.
Twelve (54.5%) of 22 free-roaming dogs in Ishigaki Island had tick infestation identified as Rhipicephalus sanguineus. There were 121 ticks recovered and consisted of 28 females, 58 males, 22 nymphs and 3 larvae. Infection of dogs possibly with canine ehrlichial pathogens was examined by both indirect immunofluorescence assay and polymerase chain reaction (PCR). Two dogs of the 13 examined were sero-positive for the human granulocytic ehrlichia agent, and one of two dogs was PCR positive for Ehrlichia platys. This dog had platelet numbers slightly lower than normal value, however, no morulae were found within platelet on peripheral blood smear stained with Giemsa.  相似文献   
107.
OBJECTIVE: To evaluate trends in feedlot cattle mortality ratios over time, by primary body system affected, and by type of animal. DESIGN: Retrospective cohort study. ANIMALS: Approximately 21.8 million cattle entering 121 feedlots in the United States during 1994 through 1999. PROCEDURES: Yearly and monthly mortality ratios were calculated. Numbers of deaths were modeled by use of Poisson regression methods for repeated measures. Relative risks of death over time and by animal type were estimated. RESULTS: Averaged over time, the mortality ratio was 12.6 deaths/1,000 cattle entering the feedlots. The mortality ratio increased from 10.3 deaths/1,000 cattle in 1994 to 14.2 deaths/1,000 cattle in 1999, but this difference was not statistically significant (P = 0.09). Cattle entering the feedlots during 1999 had a significantly increased risk (relative risk, 1.46) of dying of respiratory tract disorders, compared with cattle that entered during 1994, and respiratory tract disorders accounted for 57.1% of all deaths. Dairy cattle had a significantly increased risk of death of any cause, compared with beef steers. Beef heifers had a significantly increased risk of dying of respiratory tract disorders, compared with beef steers. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that although overall yearly mortality ratio did not significantly increase during the study, the risk of death attributable to respiratory tract disorders was increased during most years, compared with risk of death during 1994. The increased rates of fatal respiratory tract disorders may also reflect increased rates of non-fatal respiratory tract disorders, which would be expected to have adverse production effects in surviving animals.  相似文献   
108.
本文作者从实际经验出发,详细阐述了建筑物的机械排烟原理及设计施工,管理中的各项注意事项。  相似文献   
109.
发展证券资本市场可有效地推动经济快速发展 ,但林业产业上市融资明显处于低水平状态。湖南省林业产业化发展 ,客观上要求在证券资本市场上拓宽发展空间 ,为此提出林业产业发展和上市融资需采取的 6项对策与措施。  相似文献   
110.
The purpose of this study was to determine the frequency of selected pathogens in the tissues of a group of feedlot cattle with chronic disease (most often respiratory disease and/or arthritis). Samples of lung and joint tissues from 49 feedlot animals that had failed to respond to antibiotic therapy were tested by immunohistochemical staining for the antigens of Mycoplasma bovis, Haemophilus somnus, Pasteurella (Mannheimia) hemolytica, and bovine viral diarrhea virus (BVDV). Mycoplasma bovis was demonstrated in over 80% of cases, including in 45% of joints and 71% of lungs tested. Mycoplasma bovis was the only bacterial pathogen identified in the joints. Haemophilus somnus and Pasteurella (Mannheimia) haemolytica were found in 14% and 23% of cases, respectively, and were confined to the lungs in all instances. Infection with BVDV was demonstrated in over 40% of cases. Mycoplasma bovis and BVDV were the most common pathogens persisting in the tissues of these animals that had failed to respond to antibiotic therapy.  相似文献   
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